1. Field of the Invention:
The present invention relates to a synthetic resin fuel to be blown in through tuyeres for pig iron production in blast furnaces. The present invention relates also to a process for pig iron production with said synthetic resin fuel.
2. Description of the Related Art:
Blast furnaces need comparatively expensive coke for pig iron production. One way adopted to reduce coke consumption is to blow into tuyeres a variety of fuels such as natural gas, naphtha, heavy oil, tar, and pulverized coal.
There has recently been proposed a new technology of utilizing waste plastics material from the standpoint of waste disposal and recycling. For example, Japanese Patent Laid-open No. 143526/1997 discloses the use of a synthetic resin material having a specific surface area greater than 50 m.sup.2 /kg for efficient combustion in blast furnaces.
For effective use of waste plastics material as a fuel, investigations are continuing an its shape and other factors that affect combustion efficiency and stable furnace operation.
Important factors for stable furnace operation include (1) the constant size of the raceway combustion zone, (2) the stable gas flow from the combustion zone, and (3) ability to be transferred over a long distance to tuyeres without clogging. Waste plastic material as a fuel is usually used in the form of agglomerated pellets having a large specific surface area for efficient combustion. In their half-molten state, such plastic pellets easily break during transfer or pressure-feeding to tuyeres. Broken pellets cause bridging in hoppers and clogging in pipes. In other words, they present difficulties in their long-distance transfer.